1. Field of the Invention
This invention relates to the field of data processing systems. More particularly, this invention relates to the field of data transfer requests.
2. Description of the Prior Art
In data processing systems it is often necessary to transfer data from one memory to another, or between an external data source and a memory associated with the data processor. For example, in boot up codes may be stored in a slow memory such as a Flash and prior to them being used, it may be desirable to transfer them to a faster instruction memory associated with the processor. Generally, such transfers occurs via the data processor core, with a load instruction specifying a location in the Flash memory from which the data is to be read and a register in the core to which the data item is to be written, and a store instruction specifying the register in the core and the destination location in the faster instruction memory. Such a transfer is fairly slow and is expensive in instructions, taking several instructions for each data item.
The problem of data transfers being relatively slow and expensive in instructions can be particularly acute in applications such as data logging, where large amounts of data may need to be transferred to memory via a processor, at any time.